Crystaline solids have specific geometerical shape so the answer is false
Answer: an ice pack getting cold (due to ammonium nitrate dissolving in water inside the pack)
Explanation:
Endothermic reactions: These are the reactions in which energy is required in the reaction. The energy of the products are more than the energy of the reactants.
Exothermic reactions: These are the reactions in which energy is released in the reaction. The energy of the products is less than the energy of the reactants.
a) water droplets condensing on a soda can on a hot summer day : As the gaseous molecules are changing into liquid phase, energy is released and is exothermic
b) an ice pack getting cold (due to ammonium nitrate dissolving in water inside the pack) : As the temperature is decreasing , energy is absorbed by the surroundings and thus is endothermic
c) thermite reaction between iron(III) oxide and aluminium (spectacular flames are observed) : As flames are produced, the energy is released and thus is exothermic
d) freezing water to make ice cubes : As the liquid molecules are changing into solid phase, energy is released and is exothermic
Here are the possible answers for the following questions above:
1. H-CC-H (name) - C<span>. ethyne
</span>2. cyclic compound with both saturated and unsaturated characteristics - G<span>. benzene
</span>3. CnH2n - E<span>. general formula for alkenes
</span>4. reaction typical of unsaturated hydrocarbons - A<span>. addition
</span>5. CnH2n-2 - F<span>. general formula for alkynes
</span>6. series name of hydrocarbons with triple bond - D<span>. alkyne
</span>7. CnH2n+2 - B<span>. general formula of alkanes</span>
In the reduction-oxidation reaction given, Cu is reduced because it gained 2 electrons, on the other hand H2 is oxidized because it gained one electron. I hope this helps.
Balanced half-reactions:
Anode: Fe2+ -> Fe
Cathode: Mg2+ -> Mg
The cell is voltaic because the cathode has a more negative reduction potential, causing the cell potential to be positive.
The electrons flow from the anode to the cathode.
